Blue sulfur dye and process of making same.



Patented October 27, 1903.

ATENT OFFICE.

RICHARD HERZ, OF FRANKFORT-ON-THE-MAIN, GERMANY, ASSIGNOR TO LEOPOIJDOASSELLA & 00., OF FRANKFORT-ON-THE-MAIN, GERMANY.

BLUE SULFUR DYE AND PROCESS OF MAKING SAME.

SPECIFICATION forming part of Letters Patent N 0. 742,189, dated October27, 1903.

I Application filed April 17, 1903. Serial No. 153.127. (Specimens) Toall whom it may concern.- v

Be it known that I, RICHARD Hnnz, a citizen of Prussia, and a residentof Frankforton-the-Main,in the Province of Hesse-Nassau, Prussia,Germany,have invented certain new and useful Improvements in Blue SulfurDye and Processes of Making Same, of which the following is aspecification.

In the United States Letters Patent, No. 709,151, September 16, 1902, Ihave described a process of producing a blue dyestuff from paraamidotolyl para ox yphenylamin. I have now discovered that a dyestuff ofsimilar properties, but of a considerably greener shade, is obtained ifone atom of chlorin is introduced into the ortho position to thehydroxyl group of the said para amidotolyl para oxyphenylamin. Thishitherto unknown para amidotolylpara oxychlorphenylamin of the followingconstitution may be obtained by reducing the product of simultaneousoxidation of equimoleoular proportions-of chlor para amidophenol(Kohlrepp, Liebigs Annalen, Vol. 234, page 5) and orthotoluidin.

Example: 14.4 kilos chlor para amidophe- 1101 and 10.7kilosorthotoluidin are dissolved intwo hundred liters water and thirty-onekilos sulfuric acid, (66 Baum.) The solution is well cooled with ice andquickly mixed I with a solution of twenty kilos bichromate of by theaddition of bicarbonate of soda.' Theseparation may be completed bysaturation With common salt. In order to purify the product thusobtained, it is dissolved in dilute hydrochloric acid and precipitatedfrom the'filtered solution by the addition of carbonate of soda. Thethus-obtained base is difficultly soluble in water and more easilysoluble in organic solvents. It forms salts with mineral acids as wellas with caustic alkalies, which all are easily soluble in water.Alkaline. solutions are rapidly oxidized by the oxygen of the air.diluted alcohol the free base is obtained in form of colorless needlesshowing a meltingpoint of 185 centigrade.

In order to transform the amidotolyloxychlorphenylamin into a bluesulfur dyestufi, I proceed, for instance, as follows:

Example: One hundred kilos crystallized By crystallization from sodiumsulfid and fifty kilos sulfur are melted together in an iron vessel, andas soon as the sulfur is dissolved twenty-five kilosamidotolyloxychlorphenylamin are introduced at a temperature of tocentigrade. The temperature is then raised to about centigrade andmaintained during twenty-four hours. The melt is dissolved in water, thesolution is filtered, and the dyestud is precipitated by introducing acurrent of air. The thus-produced dyestuff is easily soluble in water inpresence of sodium sulfid with a blue color and dyes directgreenish-blue indigo shades on unmordanted cotton, which are fast towashing, acids, and light. By modifying the conditions of melting theshade of the coloring-matters may be varied. At higher temperaturesdyestufis of a more greenish and duller shade are obtained, While atlower temperatures or if working in an alcoholic solution more reddishand brighter shades. The general properties of the dyestuffs, however,remain essentially the same.

Having thus described my invention and in What manner the same can beperformed, what I claim is- 1. The process of producingblue cottondyestuffs by heating para amidotolyl para oxychlorphenylamin withpolysulfids substantially as described.

2. The blue sulfur dye obtained from para amidotolyl paraoxychlorphenylamin, which is a dark-blue powder nearly insoluble in purewater or alcohol, easily soluble with a] Signed atFrankfort-on-the-Main, in the dark blue color in concentrated sulfuricacid, Province of Hesse-Nassau and Kingdom of easily soluble in Water inpresence of alka- Prussia, this 2d day of April, A. D. 1903.

line sulfids and dyeing unmordanted cotton l RICHARD HERZ. 5 from such asolution greenish indigo shades Witnesses:

fast to Washing, acids and light; substantially JEAN GRUND,

as described. CARL GRUND.

